1. Field of the Invention
The present invention relates to an electron emission element irradiating an electron on a predetermined irradiation surface.
2. Description of Related Art
There is known a technique of applying an electron emission element to a recording and reproduction apparatus and an image display apparatus. Particularly, there is known a following technique of moving a position on an electron irradiation surface (hereinafter referred to as “irradiation posistion”) at which an electron from an electron source included in the electron emission element is irradiated.
For example, there is proposed a technique of changing a recording position on a recording medium by moving the recording medium in a recording apparatus performing recording and reproduction by using an electron beam. This method is disclosed in Japanese Patent Application Laid-open under No. 9-7240. There is also proposed a technique of making an irradiation position of the electron beam movable by forming the electron source on a cantilever including a piezo-electric element and controlling a displacing timing of the cantilever and an electron emission timing of the electron source. This method is disclosed in Japanese Patent Application Laid-open under No. 7-182967. Further, there is proposed a technique to moving the irradiation position of the electron beam by deflecting the electron beam itself (see T. H. P. Chang, L. P. Muray, U. Staufer and D. P. Kern, “A Scanning Tunneling Microscope Based Microcolumn System”, Jpn. J. Appl. Phys. Vol. 31 (1992) pp. 4232-4240).
However, by the above-mentioned techniques, the mechanism of the apparatus including the electron emission element and the like sometimes becomes complicated, and a configuration thereof cannot be simple. When the recording medium is moved, a complicated driving mechanism is necessary, for example. When the cantilever is used, the mechanism for driving the cantilever similarly becomes complicated. On the contrary, when the electron beam itself is deflected, a distance between a deflection unit and the electron irradiation surface has to be large in order to obtain a large deflection amount of the electron beam. Further, since the electron beam is curved, an aberration occurs to the electron beam on the electron irradiation surface, and the electron beam does not preferably converge onto the electron irradiation surface. In order to prevent it, a mechanism for correction has to be added. Therefore, the apparatus problematically becomes complicated and large.